摘要
Indigestible NDF (iNDF) is an entity in feed evaluation systems. In this study, iNDF is defined as the portion of NDF not digested after 288 h of rumen incubation in Dacron bags with 12 μm pore size. However, the method is resource demanding. The objective of this study was to elucidate the effect of lignin and hemicellulose monomers on iNDF variation within and among forage types and their ability to predict iNDF variation in linear and multiple regression models. The hypotheses were 1) lignin is expected to have high ability in describing the iNDF variation and 2) the inclusion of hemicellulose monomers will increase this ability. iNDF was determined on 50 grass-clover silages and 50 whole crop maize silages as well as 40 maize stem and 10 maize ear samples. All samples were analysed for neutral detergent fibre (NDF), Klason lignin (KL), cellulose and non-cellulose polysaccharides (NCP). Grass-clover and whole crop maize silages were analysed for acid detergent lignin (ADL). Lignin variables had the most consistent correlation to the iNDF variation throughout both correlation and regression analyses. Arabinose also showed high correlations and relationships in linear regression to iNDF and almost at same level as lignin variables. Multiple linear regression increased the accuracy for grass-clover silage and combined analysis with all forage types, with KL and/or ADL as first explanatory variables. However, the increase in accuracy is not consistent between forage types.
摘要译文
难以消化的NDF（Indf）是饲料评估系统的实体。在该研究中，Indf被定义为NDF的NDF的部分未在288小时后消化，在脱克隆袋中的折射袋中的折射袋尺寸为12μm。但是，该方法是资源要求。本研究的目的是阐明木质素和半纤维素单体对饲料类型内和预测线性和多元回归模型中的Indf变化的能力的影响。假设为1）木质素预期在描述Indf变异和2）中的含有半纤维素单体将增加这种能力。 Indf在50种草三叶草和50种整个作物玉米青贮饲料和50种玉米茎和10米玉米耳样上确定。分析所有样品以分析中性洗涤剂纤维（NDF），Klason木质素（KL），纤维素和非纤维素多糖（NCP）。分析了草三叶草和整个作物玉米木质，用于酸性洗涤剂木质素（ADL）。 Lignin变量与整个相关性和回归分析中的Indf变化具有最正常的相关性。阿拉伯糖也表现出高的相关性和关系中的线性回归与Indf和几乎与木质素变量相同的水平。多元线性回归增加了草 - 三叶草青贮和组合分析的准确性，用KL和/或ADL作为第一解释变量。但是，饲料类型之间的准确性提高不一致。
M. Rønn[a];K.E. Bach Knudsen[a];N.B. Kristensen[b];M.R. Weisbjerg[a]. Can lignin and monomer composition of fibre describe the variation in iNDF in forages?[J]. Animal Feed Science and Technology, 2022,284